N-(2-Haloalkoxy- and 2-haloalkylthiophenylsulfonyl)-N&#39;-(halogenatedpyridinyl)ureas

ABSTRACT

N-Phenylsulfonyl-N&#39;-pyrimidinylureas of the general formula ##STR1## and the salts thereof with amines, alkali metal or alkaline earth metal bases or with quaternary ammonium bases, have good pre- and postemergence selective herbicidal and growth regulating properties. In the above formula 
     A is difluoromethyl, trifluoromethyl, 1,1,2,2-tetrafluoroethyl, 1,1,2-trifluoro-2-chloro-ethyl or 1,1,2,3,3,3-hexafluoropropyl, 
     X is oxygen, sulfur, a sulfinyl or sulfonyl bridge, 
     Z is oxygen or sulfur, 
     R 2  is hydrogen, halogen, C 1  -C 5  alkyl, C 2  -C 5  alkenyl, C 1  -C 4  haloalkyl, or a radical --Y--R 5 , --COOR 6 , --NO 2  or --CO--NR 7  --R 8 , 
     R 3  is hydrogen, C 1  -C 4  alkyl, C 1  -C 4  alkoxy, C 1  -C 4  alkylthio, C 1  -C 4  haloalkyl, halogen or alkoxyalkyl of at most 4 carbon atoms, 
     R 4  is halogen, C 2  -C 4  alkyl, C 3  -C 4  alkoxy, C 1  -C 4  haloalkyl or ethoxymethyl, 
     R 5  and R 6 , each independently of the other, are C 1  -C 5  alkyl, C 2  -C 5  alkenyl or C 2  -C 6  alkynyl, 
     R 7  and R 8 , each independently of the other, are hydrogen, C 1  -C 5  alkyl, C 2  -C 5  alkenyl or C 2  -C 6  alkynyl, and 
     Y is oxygen, sulfur, a sulfinyl or sulfonyl bridge.

CROSS REFERENCE TO RELATED APPLICATIONS

This is a continuation-in-part of application Ser. No. 423,352 filed onSept. 24, 1982, now abandoned which is a divisional of application Ser.No. 282,779 filed on July 13, 1981 now abandoned.

The present invention relates to novelN-phenylsulfonyl-N'-pyrimidinylureas having herbicidal and plantgrowth-regulating properties, to the production thereof, to compositionscontaining them, and to the use thereof for controlling weeds, inparticular selectively, in crops of useful plants, or for regulating andinhibiting plant growth.

The N-phenylsulfonyl-N'-pyrimidinylureas of this invention have thegeneral formula I ##STR2## wherein A is difluoromethyl, trifluoromethyl,1,1,2,2-tetrafluoroethyl, 1,1,2-trifluoro-2-chloro-ethyl or1,1,2,3,3,3-hexafluoropropyl,

X is oxygen, sulfur, a sulfinyl or sulfonyl bridge,

Z is oxygen or sulfur,

R₂ is hydrogen, halogen, C₁ -C₅ alkyl, C₂ -C₅ alkenyl, C₁ -C₄ haloalkyl,or a radical --Y--R₅, --COOR₆, --NO₂ or --CO--NR₇ --R₈,

R₃ is hydrogen, C₁ -C₄ alkyl, C₁ -C₄ alkoxy, C₁ -C₄ alkylthio, C₁ -C₄haloalkyl, halogen or alkoxyalkyl of at most 4 carbon atoms,

R₄ is halogen, C₂ -C₄ alkyl, C₃ -C₄ alkoxy, C₁ -C₄ haloalkyl orethoxymethyl,

R₅ and R₆, each independently of the other, are C₁ -C₅ alkyl, C₂ -C₅alkenyl or C₂ -C₆ alkynyl,

R₇ and R₈, each independently of the other, are hydrogen, C₁ -C₅ alkyl,C₂ -C₅ alkenyl or C₂ -C₆ alkynyl, and

Y is oxygen, sulfur, a sulfinyl or sulfonyl bridge, and salts of thesecompounds.

Herbicidally active ureas, triazines and pyrimidines are generally knownin the art. Arylsulfamoyl-heterocyclylaminocarbamoyl compounds withherbicidal and plant growth-regulating action have recently beendescribed, for example in European patent publications 1514 and 1515,U.S. Pat. No. 4,127,405, German Offenlegungsschrift No. 2 715 786 orFrench patent specification No. 1 468 747.

In the above definitions, alkyl denotes straight-chain or branchedalkyl, e.g. methyl, ethyl, n-propyl, isopropyl, the four isomers ofbutyl, n-amyl, isoamyl, 2-amyl, 3-amyl, n-hexyl or isohexyl.

Alkoxy denotes methoxy, ethoxy, n-propyloxy, isopropyloxy and the fourbutyloxy isomers, and is, in particular, methoxy, ethoxy orisopropyloxy.

Alkylthio is e.g. methylthio, ethylthio, n-propylthio, isopropylthio andn-butylthio, with methylthio and ethylthio being preferred.

Examples of alkenyl radicals are vinyl, allyl, isopropenyl, 1-propenyl,1-butenyl, 2-butenyl, 3-butenyl, 1-isobutenyl, 2-isobutenyl, 1-pentenyl,2-pentenyl, 3-pentenyl and 4-pentenyl, with vinyl, allyl and 4-pentenylbeing preferred.

Alkylsulfinyl is e.g. methylsufinyl, ethylsulfinyl, n-propylsulfinyl andn-butylsulfinyl, with methylsulfinyl and ethylsulfinyl being preferred.

Alkylsulfonyl is e.g. methylsulfonyl, ethylsulfonyl, n-propylsulfonyland n-butylsulfonyl, with methylsulfonyl and ethylsulfonyl beingpreferred.

Halogen in the definitions of R₁ and R₂ and in haloalkyl, haloalkoxy,haloalkylsulfinyl, haloalkylsulfonyl and haloalkylthio is fluorine,chlorine and bromine, with fluorine and chlorine being preferred.

A haloalkyl radical is a radical which carries one or more halogenatoms. Preferably several hydrogen atoms, and optionally even allhydrogen atoms, of the alkyl radicals are replaced by halogen atoms.

The invention also comprises the salts which the compounds of formula Iare able to form with amines, alkali metal and alkaline earth metalbases or quaternary ammonium bases.

Preferred salt-forming alkali metal and alkaline earth metal hydroxidesare the hydroxides of lithium, sodium, potassium, magnesium or calcium,most preferably of sodium or potassium.

Examples of suitable salt-forming amines are primary, secondary andtertiary aliphatic and aromatic amines such as methylamine, ethylamine,propylamine, isopropylamine, the four isomeric butylamines,dimethylamine, diethylamine, diethanolamine, dipropylamine,diisopropylamine, di-n-butylamine, pyrrolidine, piperidine, morpholine,trimethylamine, triethylamine, tripropylamine, quinuclidine, pyridine,quinoline and isoquinoline. Preferred amines are ethylamine,propylamine, diethylamine or triethylamine, with isopropylamine anddiethanolamine being most preferred.

Examples of quaternary ammonium bases are, in general, the cations ofhaloammonium salts, e.g. the tetramethylammonium cation, thetrimethylbenzylammonium cation, the triethylbenzylammonium cation, thetetraethylammonium cation, the trimethylethylammonium cation, and alsothe ammonium cation.

Preferred compounds of the formula I are those in which

(a) Z is oxygen and

(b) R₃ and R₄ together contain not more than 4 carbon atoms.

Preferred compounds in group (a) are those in which the radical --X--Ais in the 2- or 3-position to the sulfonyl radical. Among thesepreferred compounds further preference attaches to those compounds inwhich the radical --X--A is in the 2-position.

A further preference in connection with compounds of the above subgroupconsists in the feature that the radicals R₃ and R₄ together contain atmost 4 carbon atoms. Accordingly, a particularly preferred group ofcompounds of formula I is the group in which only one radical --X--A isin the 2-position to the sulfonyl radical, and R₃ and R₄ togethercontain not more than 4 carbon atoms.

Preferred compounds of this group are those in which R₂ is in the 5- or6-positon to the sulfonyl group.

Among these preferred compounds, preference attaches in turn to thosecompounds in which R₂ is hydrogen, fluorine, nitro or COOR₆.

Further preferred compounds within this last mentioned group are thosein which X is oxygen or sulfur. Of these compounds the most preferredare in turn those compounds in R₂ are hydrogen, R₃ is chlorine,fluorine, methyl, chloromethyl, ethoxy, isopropyloxy, ethyl or methoxy,and R₄ is ethyl.

Two further preferred subgroups of compounds within this last groupcomprises those compounds in which

(α) the bridge member X is oxygen and

(β) the radical A is --CF₂ G, wherein G is hydrogen or fluorine.

Of the compounds of formula I in which Z is sulfur, those compounds arepreferred in which X is oxygen or sulfur and R₃ is C₁ -C₃ alkyl, C₁ -C₃alkoxy or C₁ -C₃ alkylthio, and R₄ is C₂ -C₄ alkyl or C₃ -C₄ alkoxy andR₃ and R₄ contain together at most 4 carbon atoms, and A is --CHF₂ or--CF₂ CHF₂, and the radical --X--A is in the 2-position.

Preferred individual compounds are:

N-(2-difluoromethoxyphenylsulfonyl)-N'-(4-chloro-6-methylpyrimidin-2-yl)urea,

N-(2-difluoromethylthiophenylsulfonyl)-N'-(4-chloro-6-methoxy-pyrimidin-2-yl)ureaand

N-(2-difluoromethoxyphenylsulfonyl)-N'-(4-chlor-6-methoxy-pyrimidin-2-yl)urea.

The process for obtaining the compounds of formula I is carried out inan inert organic solvent.

In a first process, the compounds of the formula I are obtained byreacting a phenylsulfonamide of the formula II ##STR3## wherein A, R₂and X are as defined for formula I, in the presence of a base, with aN-pyrimidinylcarbamate of the formula III ##STR4## wherein R₃, R₄ and Zare as defined for formula I.

In a second process, compounds of formula I are obtained by reacting aphenylsulfonylisocyanate or phenylsulfonylisothiocyanate of the formulaIV ##STR5## wherein A, R₂, X and Z are as defined for formula I,optionally in the presence of a base, with an amine of the formula V##STR6## wherein R₃ and R₄ are as defined for formula I.

In a further process, the compounds of formula I are obtained byreacting a sulfonamide of the formula II above, optionally in thepresence of a base, with an isocyanate or isothiocyanate of the formulaVI ##STR7## wherein R₃, R₄ and Z are as defined for formula I.

Finally, the compound of formula I can also be obtained by reacting aN-phenylsulfonylcarbamate of the formula VII ##STR8## wherein A, R₂ andX are as defined for formula I, with an amine of the formula V above.

If desired, the ureas of formula I can be converted into salts withamines, alkali metal or alkaline earth metal hydroxides or quaternaryammonium bases. This conversion is carried out e.g. by reacting thecompounds of formula I with the equimolar amount of a base and removingthe solvent by evaporation.

Some of the starting materials of the formulae II, IV and VII are noveland can be prepared by the following methods.

The novel sulfonamides of formula II used as intermediates are obtainedfrom the corresponding anilines by diazotisation and replacement of thediazo group, with sulfur dioxide, in the presence of a catalyst such ascopper(I) chloride, in hydrochloric acid or acetic acid, and reactingthe resultant phenylsulfonyl chloride with ammonium hydroxide solution.

The phenylsulfonylisocyanates of the formula IV can be obtained byreacting the sulfonamides of the formula II with phosgene, in thepresence of butylisocyanate in a chlorinated hydrocarbon as solvent, atreflux temperature. Similar reactions are described in "Newer Methods ofPreparative Organic Chemistry", Vol. VI, 223-241, Academic Press, NewYork and London.

The isothiocyanates of the formula IV are obtained by treating thesulfonamides of formula II with carbon disulfide and potassium hydroxideand by subsequent reaction of the dipotassium salt with phosgene. Suchprocesses are described in Arch. Pharm. 229, 174 (1966).

The N-phenylsulfonylcarbamates of the formula VII are obtained byreacting the sulfonamides of the formula II with diphenyl carbonate inthe presence of a base. Similar processes are described in Japanesepatent specification 61 169.

The starting materials of the formulae III, V and VI are known or theycan be prepared by known methods.

Isocyanates of the formula VI can be prepared by reacting amines of theformula V with oxalyl chloride in a chlorinated hydrocarbon as solvent.Amines of the formula V are known and some are commercially available,or they can be prepared by known methods, q.v. "The Chemistry ofHeterocyclic Compounds", Vol. XIV, Interscience Publishers, New York,London.

It is expedient to carry out the reactions for obtaining compounds offormula I in aprotic, inert organic solvents such as methylene chloride,tetrahydrofurane, acetonitrile, dioxane or toluene.

The reaction temperatures are preferably in the range from -20° and+120° C. The reactions are normally slightly exothermic and can becarried out at room temperature. To shorten the reaction time or also toinitiate the reaction it is expedient to heat the reaction mixturebriefly to boiling point. The reaction times can also be shortened byaddition of a few drops of a base or isocyanate as catalyst.

The final products can be isolated by concentrating the reaction mixtureand/or removing the solvent by evaporation, and by recrystallisation orby triturating the solid residue in solvents in which it is poorlysoluble, such as ether, aromatic hydrocarbons or chlorinatedhydrocarbons.

The compounds of formula I are stable compounds, and no protectivemeasures are required for handling them.

The compounds of formula I have pronounced plant growth-regulating,especially plant growth-inhibiting, properties. The growth of bothmonocots and dicots is inhibited. Thus, for example, the compounds offormula I selectively inhibit the growth of leguminosae which arefrequently planted as cover crops in tropical regions, so that, whilesoil erosion between cultivated plants is prevented, the cover cropscannot compete with the cultivated plants.

Further, the compounds of formula I are suitable for preventing storedpotatoes from seeding. During winter storage, potatoes often developsprouts which result in shrinkage, weight loss, and rot.

When the compounds of formula I are applied in higher rates ofapplication, all tested plants are so damaged in their development thatthey wither. When used in lower rates of application, the compounds offormula I have good selective growth-inhibiting and selective herbicidalproperties which make them most suitable for use in crops of usefulplants, especially in cereals, cotton, soybeans, maize and rice. In somecases damage is also caused to weeds which have up to now have only beencontrolled with total herbicides.

The mode of action of these compounds is unusual. Many aretranslocatable, i.e. they are absorbed by the plant and transported toother parts of it where they then deploy their action. The unusualfeature of the compounds is that they do not only take the path throughthe vascular bundle in the ligneous part from the roots to the leaves,but can also be translocated through the sieve tubes in the bast part ofthe leaves back into the roots. Thus, for example, it is possible todamage perennial weeds to the very roots by surface treatment. Comparedwith other herbicides and growth regulators, the novel compounds of theformula I are effective even when used in very low rates of application.

The invention also relates to herbicidal and plant growth-regulatingcompositions which contain a novel compound of the formula I, and alsoto methods of controlling weeds pre- and postemergence and of inhibitingthe growth of monocots and dicots, especially grasses, tropical covercrops and tobacco plant suckers.

The compounds of the formula I are used in unmodified form or preferablytogether with the adjuvants conventionally employed in the art offormulation, and are therefore formulated in known manner toemulsifiable concentrates, directly sprayable or dilutable solutions,dilute emulsions, wettable powders, soluble powders, dusts, granulates,and also encapsulations in e.g. polymer substances. The methods ofapplication, such as spraying, atomising, dusting, scattering orpouring, are chosen in accordance with the intended objectives and theprevailing circumstances, just like the nature of the compositions.

The formulations, i.e. the compositions or preparations containing thecompound (active ingredient) of the formula I and, where appropriate, asolid or liquid adjuvant, are prepared in known manner, e.g. byhomogeneously mixing and/or grinding the active ingredients withextenders, e.g. solvents, solid carriers and, where appropriate,surface-active compounds (surfactants).

Suitable solvents are: aromatic hydrocarbons, preferably the fractionscontaining 8 to 12 carbon atoms, e.g. xylene mixtures or substitutednaphthalenes, phthalates such as dibutyl phthalate or dioctyl phthalate,aliphatic hydrocarbons such as cyclohexane or paraffins, alcohols andglycols and their ethers and esters, such as ethanol, ethylene glycol,ethylene glycol monomethyl or monoethyl ether, ketones such ascyclohexanone, strongly polar solvents such as N-methyl-2-pyrrolidone,dimethyl sulfoxide or dimethyl formamide, as well as epoxidisedvegetable oils such as epoxidised coconut oil or soybean oil; or water.

The solid carriers used e.g. for dusts and dispersible powders arenormally natural mineral fillers such as calcite, talcum, kaolin,montmorillonite or attapulgite. In order to improve the physicalproperties it is also possible to add highly dispersed silicic acid orhighly dispersed absorbent polymers. Suitable granulated adsorptivecarriers are porous types, for example pumice, broken brick, sepioliteor bentonite; and suitable nonsorbent carriers are materials such ascalcite or sand. In addition, a great number of pregranulated materialsof inorganic or organic nature can be used, e.g. especially dolomite orpulverised plant residues.

Depending on the nature of the compound of formula I to be formulated,suitable surface-active compounds are nonionic, cationic and/or anionicsurfactants having good emulsifying, dispersing and wetting properties.The term "surfactants" will also be understood as comprising mixtures ofsurfactants.

Suitable anionic surfactants can be both water-soluble soaps andwater-soluble synthetic surface-active compounds.

Suitable soaps are the alkali, alkaline earth or unsubstituted orsubstituted ammonium salts of higher fatty acids (C₁₀ -C₂₂), e.g. thesodium or potassium salts of oleic or stearic acid, or of natural fattyacid mixtures which can be obtained e.g. from coconut oil or tallow oil.Mention may also be made of fatty acid methyltaurin salts.

More frequently, however, so-called synthetic surfactants are used,especially fatty sulfonates, fatty sulfates, sulfonated benzimidazolederivatives or alkylarylsulfonates.

The fatty sulfonates or sulfates are usually in the form of alkali,alkaline earth or unsubstituted or substituted ammonium salts andcontain a C₈ -C₂₂ alkyl radical which also includes the alkyl moiety ofacyl radicals, e.g. the sodium or calcium salt of lignosulfonic acid, ofdodecylsulfate or of a mixture of fatty alcohol sulfates obtained fromnatural fatty acids. These compounds also comprise the salts of sulfuricacid esters and sulfonic acids of fatty alcohol/ethylene oxide adducts.The sulfonated benzimidazole derivatives preferably contain 2 sulfonicacid groups and one fatty acid radical containing 8 to 22 carbon atoms.Examples of alkylarylsulfonates are the sodium, calcium ortriethanolamine salts of dodecylbenzenesulfonic acid,dibutylnaphthalenesulfonic acid, or of a naphthalenesulfonicacid/formaldehyde condensation product. Also suitable are correspondingphosphates, e.g. salts of the phosphoric acid ester of an adduct ofp-nonylphenol with 4 to 14 moles of ethylene oxide.

Non-ionic surfactants are preferably polyglycol ether derivatives ofaliphatic or cycloaliphatic alcohols, or saturated or unsaturated fattyacids and alkylphenols, said derivatives containing 3 to 30 glycol ethergroups and 8 to 20 carbon atoms in the (aliphatic) hydrocarbon moietyand 6 to 18 carbon atoms in the alkyl moiety of the alkylphenols.

Further suitable non-ionic surfactants are the water-soluble adducts ofpolyethylene oxide with polypropylene glycol,ethylenediaminepolypropylene glycol and alkylpolypropylene glycolcontaining 1 to 10 carbon atoms in the alkyl chain, which adductscontain 20 to 250 ethylene glycol ether groups and 10 to 100 propyleneglycol ether groups. These compounds usually contain 1 to 5 ethyleneglycol units per propylene glycol unit.

Representative examples of non-ionic surfactants arenonylphenol-polyethoxyethanols, castor oil polyglycol ethers,polypropylene/polyethylene oxide adducts,tributylphenoxypolyethoxyethanol, polyethylene glycol andoctylphenoxypolyethoxyethanol. Fatty acid esters of polyoxyethylenesorbitan and polyoxyethylene sorbitan trioleate are also suitablenon-ionic surfactants.

Cationic surfactants are preferably quaternary ammonium salts whichcontain, as N-substituent, at least one polyglycol ether or C₈ -C₂₂alkyl radical and, as further substituents, lower unsubstituted orhalogenated alkyl, benzyl or lower hydroxyalkyl radicals. The salts arepreferably in the form of halides, methylsulfates or ethylsulfates, e.g.stearyltrimethylammonium chloride orbenzyldi(2-chloroethyl)ethylammonium bromide.

The surfactants customarily employed in the art of formulation aredescribed e.g. in the following publications: "McCutcheon's Detergentsand Emulsifiers Annual", MC Publishing Corp., Ridgewood, N.J., 1979;Sisley and Wood, "Encyclopedia of Surface Active Agents", ChemicalPublishing Co. Inc., New York, 1964.

The pesticidal formulations usually contain 0.1 to 95%, preferably 0.1to 80%, of a compound of the formula I, 1 to 99.9% of a solid or liquidadjuvant, and 0 to 25%, preferably 0.1 to 25%, of a surfactant.

Preferred formulations are composed in particular of the followingconstituents (%=percentage by weight):

Solutions

active ingredient: 1 to 30%, preferably 5 to 20%

solvent: 99 to 0%, preferably 95 to 0%

surfactants: 0 to 99%, preferably 0 to 95%

Emulsifiable concentrates

active ingredient: 1 to 20%, preferably 5 to 10%

surfactant: 5 to 30%, preferably 10 to 20%

liquid carrier: 50 to 94%, preferably 70 to 85%

Dusts

active ingredient: 0.1 to 10%, preferably 0.1 to 1%

solid carrier: 99.9 to 90%, preferably 99.9 to 99%

Suspension concentrates

active ingredient: 5 to 75%, preferably 10 to 50%

water: 94 to 25%, preferably 90 to 30%

surfactant: 1 to 40%, preferably 2 to 30%

Wettable powders

active ingredeint: 0.5 to 90%, preferably 1 to 80%

surfactant: 0.5 to 20%, preferably 1 to 15%

solid carrier: 5 to 95%, preferably 15 to 90%

Granulates

active ingredient: 0.5 to 30%, preferably 3 to 15%

solid carrier: 99.5 to 70%, preferably 97 to 85%.

Whereas commercial products will be preferably formulated asconcentrates, the end user will normally employ dilute formulations. Theformulations can be diluted to a concentration as low as 0.001%. Therates of application are normally 0.01 to 10 kg a.i./ha, preferably0.025 to 5 kg a.i./ha.

The compositions can also contain further ingredients such asstabilisers, antifoams, viscosity regulators, binders, adhesives, aswell as fertilisers or other active compounds, in order to attainspecial effects.

PREPARATORY EXAMPLES EXAMPLE 1

(a) 2-Difluoromethoxyphenylsulfonyl chloride

While cooling at 0° C., 101.2 g of a 40% solution of sodium hydrogensulfite are added dropwise to a solution of 6.4 g of copper sulfate in276 ml of 36% hydrochloric acid and 72 ml of water. To the resultantsolution is then made the simultaneous dropwise addition of 101.2 g of a40% solution of sodium hydrogen sulfite and a diazonium salt solutionwhich has been cooled to -10° C. and obtained by the dropwise addition,with cooling, of 28.8 g of sodium nitrite in 44 ml of water to asolution of 39 ml of water, 84 ml of 36% hydrochloric acid and 63.7 g of2-difluoromethoxyaniline. During this addition the temperature of thereaction mixture rises to 30° C., accompanied by the simultaneousevolution of gas. The reaction mixture is stirred for 18 hours,whereupon a brown oil precipitates. The organic phase is separated andthe aqueous phase is extracted with methylene chloride. The organicphases are combined and evaporated to dryness, affording, as crudeproduct, 80.3 g of 2-difluoromethoxysulfonyl chloride in the form of abrown oil.

(b) 2-Difluoromethoxyphenylsulfonamide

To a mixture of 250 ml of methylene chloride, 250 ml of water and 250 mlof 30% ammonia solution is slowly added a solution of 80.3 g of crude2-difluoromethoxyphenylsulfonyl chloride in 50 ml of methylene chloride.After the exothermic reaction has subsided, the reaction mixture isrefluxed for 2 hours. The organic phase is washed with water, dried oversodium sulfate, and evaporated to dryness. Recrystallisation frommethanol yield 40.5 g of 2-difluoromethoxyphenylsulfonamide with amelting point of 128°-130° C.

The following novel intermediates, specially developed for the synthesisof compounds of formula I, are obtained in analogous manner.

                  TABLE 1                                                         ______________________________________                                         ##STR9##                                                                                                             Physical                                                               Position                                                                             data                                  R.sub.2   X      A           m   of XA  °C.                            ______________________________________                                        6-COOCH.sub.2 CH.sub.3                                                                  O      CHF.sub.2   1   2                                            6-COOCH.sub.2 CH.sub.3                                                                  S      CHF.sub.2   1   2                                            6-COOCH.sub.3                                                                           SO     CHF.sub.2   1   2                                            6-COOCH.sub.2 CH.sub.3                                                                  SO.sub.2                                                                             CHF.sub.2   1   2                                            5-CF.sub.3                                                                              O      CHF.sub.2   1   2                                            5-CF.sub.3                                                                              S      CHF.sub.2   1   2                                            5-CF.sub.3                                                                              SO     CHF.sub.2   1   2                                            5-CF.sub.3                                                                              SO.sub.2                                                                             CHF.sub.2   1   2                                            6-NO.sub.2                                                                              O      CHF.sub.2   1   3                                            6-COOCH.sub.2 CH.sub.3                                                                  O      CF.sub.3    1   2                                            6-COOCH.sub.2 CH.sub.3                                                                  S      CF.sub.3    1   2                                            6-COOCH.sub.2 CH.sub.3                                                                  SO     CF.sub.3    1   2                                            6-COOCH.sub.2 CH.sub.3                                                                  SO.sub.2                                                                             CF.sub.3    1   2                                            6-COOCH.sub.2 CH.sub.3                                                                  O      CF.sub.2 CHF.sub.2                                                                        1   2                                            6-COOCHCH.sub.3                                                                         S      CF.sub.2CHF.sub.2                                                                         1   2                                            6-COOCH.sub.2 CH.sub.3                                                                  SO     CF.sub.2CHF.sub.2                                                                         1   2                                            6-COOCH.sub.2 CH.sub.3                                                                  SO.sub.2                                                                             CF.sub.2CHF.sub.2                                                                         1   2                                            6-COOC.sub.2 H.sub.5                                                                    O      CF.sub.3    1   3                                            6-COOC.sub.2 H.sub.5                                                                    S      CF.sub.3    1   3                                            6-COOC.sub.2 H.sub.5                                                                    SO     CF.sub.3    1   3                                            6-COOC.sub.2 H.sub.5                                                                    SO.sub.2                                                                             CF.sub.3    1   3                                            6-COOCH.sub.3                                                                           O      CHF.sub.2   1   2                                            6-NO.sub.2                                                                              O      CHF.sub.2   1   2                                            ______________________________________                                    

EXAMPLE 2

(a) N-(2-Difluoromethoxyphenylsulfonyl)-N'-methylurea.

The 2-difluoromethoxyphenylsulfonamide obtained in Example 1b issuspended in 400 ml of methylene chloride. Then 16.3 g of methylisocyanate are added and 28.2 g of triethylamine are subsequently addeddropwise over 15 minutes to form a clear solution. The solution isevaporated to dryness, and the residue is dissolved in 5% sodiumcarbonate solution. N-(2-difluoromethoxyphenylsulfonyl)-N'-methylureawith a melting point of 228°-229° C., is precipitated from the solutionby acidification with 10% hydrochloric acid.

Yield: 43.2 g.

(b) 2-Difluoromethoxyphenylsulfonyl isocyanate

43.2 g of N-(2-pentafluoromethoxyphenylsulfonyl)-N'-methylurea aresuspended in 1300 ml of chlorobenzene and made absolute by distillingoff about 100 ml of solvent as an azeotrope. Then 48 g of phosgene areintroduced at 120°-130° C. over 3 hours. The chlorobenzene is thencompletely distilled off, affording 34.2 g of2-difluoromethoxyphenylsulfonyl isocyanate in the form of an almostcolourless oil.

(c)N-(2-Difluoromethoxyphenylsulfonyl)-N'-(4-chloro-6-methyl-pyrimidin-2-yl)urea

34.2 g of 2-difluoromethoxyphenylsulfonyl isocyanate and 19.7 g of2-amino-4-chloro-6-methyl-pyrimidine are stirred in 40 ml of dioxane for3 hours at 90°-100° C. The solution is then cooled to 20° C., filtered,and concentrated to about 1/4 of its volume. After addition of ether,32.9 g ofN-(2-difluoromethoxyphenylsulfonyl)-N'-(4-chloro-6-methyl-pyrimidin-2-yl)ureacrystallise from the residue.

Melting point: 190°-191° C.

The compounds of formula I listed in the following tables are preparedin similar manner.

                  TABLE 2                                                         ______________________________________                                         ##STR10##                                                                                                             Phys-                                                                         ical                                                                          data                                 No.  A            R.sub.3 R.sub.4    X   (°C.)                         ______________________________________                                        1    CF.sub.2CHF.sub.2                                                                          CH.sub.3                                                                              C.sub.2 H.sub.5                                                                          O   m.p.                                                                          147-                                                                          148°                          2    CF.sub.3     CH.sub.3                                                                              Cl         O                                        3    CHF.sub.2    OCH.sub.3                                                                             CH(CH.sub.3).sub.2                                                                       S                                        4    CHF.sub.2    C.sub.2 H.sub.5                                                                       Cl         S                                        5    CHF.sub.2    CH.sub.3                                                                              Cl         S   m.p.                                                                          194-                                                                          195°                          6    CHF.sub.2    CH.sub.3                                                                              F          S   m.p.                                                                          186-                                                                          187°                          7    CHF.sub.2    CH.sub.3                                                                              Br         S                                        8    CHF.sub.2    OC.sub.2 H.sub.5                                                                      C.sub.2 H.sub.5                                                                          S                                        9    CHF.sub.2    SCH.sub.3                                                                             C.sub.2 H.sub.5                                                                          S                                        10   CHF.sub.2    CH.sub.3                                                                              CF.sub.3   S                                        11   CHF.sub.2    CH.sub.3                                                                              CH.sub.2 Cl                                                                              S                                        12   CHF.sub.2    OCH.sub.3                                                                             CH.sub.2 Cl                                                                              S                                        13   CHF.sub.2    OCH.sub.3                                                                             Cl         S   m.p.                                                                          159-                                                                          164°                          14   CHF.sub.2    Cl      Cl         S   m.p.                                                                          201-                                                                          202°                          15   CHF.sub.2    OCH.sub.3                                                                             OCH(CH.sub.3).sub.2                                                                      S                                        16   CHF.sub.2    OCH.sub.3                                                                             CH.sub.2 F S                                        17   CHF.sub.2    CH.sub.3                                                                              CH.sub.2 F S                                        18   CHF.sub.2    OCH.sub.3                                                                             CF.sub.3   S                                        19   CHF.sub.2    OCH.sub.3                                                                             C.sub.3 H.sub.7i                                                                         O   m.p.                                                                          141-                                                                          143°                          20   CHF.sub.2    C.sub.2 H.sub.5                                                                       Cl         O                                        21   CHF.sub.2    CH.sub.3                                                                              Cl         O   m.p.                                                                          190-                                                                          191°                          22   CHF.sub.2    CH.sub.3                                                                              F          O   m.p.                                                                          174-                                                                          176°                          23   CHF.sub.2    CH.sub.3                                                                              Br         O                                        24   CHF.sub.2    OC.sub.2 H.sub.5                                                                      C.sub.2 H.sub.5                                                                          O                                        25   CHF.sub.2    SCH.sub.3                                                                             C.sub.2 H.sub.5                                                                          O                                        26   CHF.sub.2    CH.sub.3                                                                              CF.sub.3   O                                        27   CHF.sub.2    CH.sub.3                                                                              CH.sub.2 Cl                                                                              O                                        28   CHF.sub.2    OCH.sub.3                                                                             CH.sub.2 Cl                                                                              O                                        29   CHF.sub.2    OCH.sub.3                                                                             Cl         O   m.p.                                                                          165-                                                                          167°                          30   CHF.sub.2    Cl      Cl         O   m.p.                                                                          183-                                                                          188°                          31   CHF.sub.2    OCH.sub.3                                                                             OCH(CH.sub.3).sub.2                                                                      O   m.p.                                                                          72-                                                                           74°                           32   CHF.sub.2    OCH.sub.3                                                                             CH.sub.2 F O   m.p.                                                                          175-                                                                          176°                          33   CHF.sub.2    CH.sub.3                                                                              CH.sub.2 F O                                        34   CHF.sub.2    OCH.sub.3                                                                             CF.sub.3   O   m.p.                                                                          152-                                                                          154°                          35   CF.sub.2CHF.sub.2                                                                          CH.sub.3                                                                              Cl         O                                        36   CF.sub.2CHF.sub.2                                                                          OCH.sub.3                                                                             Cl         O   m.p.                                                                          164-                                                                          165°                          37   CF.sub.2 CHFCl                                                                             CH.sub.3                                                                              Cl         O   m.p.                                                                          177-                                                                          179°                          38   CF.sub.2CHFCl                                                                              OCH.sub.3                                                                             Cl         O   m.p.                                                                          164-                                                                          165°                          39   CHF.sub.2    OCH.sub.3                                                                             C.sub.2 H.sub.5                                                                          O   m.p.                                                                          151-                                                                          153°                          40   CHF.sub.2    OCH.sub.3                                                                             CH.sub.2OC.sub.2 H.sub.5                                                                 O   m.p.                                                                          144-                                                                          145°                          41   CHF.sub.2    OC.sub.2 H.sub.5                                                                      CH.sub.2 F O   m.p.                                                                          147-                                                                          148°                          42   CHF.sub.2    OC.sub.2 H.sub.5                                                                      Cl         O   m.p.                                                                          135-                                                                          137°                          ______________________________________                                    

                  TABLE 3                                                         ______________________________________                                         ##STR11##                                                                                 Position                      Physical                           No.  A       of XA     R.sub.2                                                                            R.sub.3                                                                             R.sub.4                                                                            X   data (°C.)                  ______________________________________                                        50   CHF.sub.2                                                                             2         5-F  CH.sub.3                                                                            Cl   O                                      51   CHF.sub.2                                                                             2         5-F  CH.sub.3                                                                            C.sub.2 H.sub.5                                                                    S                                      52   CHF.sub.2                                                                             2         5-F  CH.sub.3                                                                            C.sub.2 H.sub.5                                                                    O                                      53   CHF.sub.2                                                                             2         5-F  OCH.sub.3                                                                           Cl   O   m.p.                                                                          160-161°                    54   CHF.sub.2                                                                             2         5-F  CH.sub.3                                                                            Br   O                                      55   CHF.sub.2                                                                             2         5-F  CH.sub.3                                                                            F    O                                      56   CHF.sub.2                                                                             2         5-F  C.sub.2 H.sub.5                                                                     Cl   O                                      57   C.sub.2 F.sub.5                                                                       2         5-F  CH.sub.3                                                                            Cl   O                                      58   CHF.sub.2                                                                             2         6-F  CH.sub.3                                                                            Cl   O                                      59   CHF.sub.2                                                                             2         6-F  CH.sub.3                                                                            Br   O                                      60   CHF.sub.2                                                                             2         6-F  OCH.sub.3                                                                           C.sub.2 H.sub.5                                                                    O                                      61   CHF.sub.2                                                                             2         6-F  C.sub.2 H.sub.5                                                                     Cl   O                                      62   CHF.sub.2                                                                             2         6-F  CH.sub.3                                                                            Cl   S                                      63   CHF.sub.2                                                                             2         6-F  CH.sub.3                                                                            Br   S                                      64   CHF.sub.2                                                                             2         6-F  OCH.sub.3                                                                           Cl   S                                      65   CHF.sub.2                                                                             2         6-F  CH.sub.3                                                                            C.sub.2 H.sub.5                                                                    S                                      66   CHF.sub.2                                                                             2         5-Cl CH.sub.3                                                                            Cl   O                                      67   CHF.sub.2                                                                             2         5-Cl OCH.sub.3                                                                           Cl   O                                      68   CHF.sub.2                                                                             2         5-Cl CH.sub.3                                                                            Cl   O   m.p. 182°                                                              (decomp.)                          69   CHF.sub.2                                                                             2         5-Cl OCH.sub.3                                                                           Cl   O   m.p.                                                                          170-172°                    ______________________________________                                    

                  TABLE 4                                                         ______________________________________                                         ##STR12##                                                                    No.   A          E      R.sub.3   R.sub.4                                                                            X                                      ______________________________________                                        80    CHF.sub.2  CH     OCH.sub.3 C.sub.2 H.sub.5                                                                    O                                      81    CHF.sub.2  CH     OCH.sub.3 C.sub.2 H.sub.5                                                                    S                                      ______________________________________                                    

EXAMPLE 3 Formulation examples (throughout, percentages are by weight)

    ______________________________________                                        (a) Wettable powders                                                                            (a)      (b)      (c)                                       ______________________________________                                        active ingredient 20%      60%       0.5%                                     sodium lignosulfonate                                                                           5%       5%       5%                                        sodium laurylsulfate                                                                            3%       --       --                                        sodium diisobutylnaphthalene-                                                                   --       6%       6%                                        sulfonate                                                                     octylphenol polyethylene glycol                                                                 --       2%       2%                                        ether (7-8 moles of ethylene                                                  oxide)                                                                        highly dispersed silicic acid                                                                   5%       27%      27%                                       kaolin            67%      --       --                                        sodium chloride   --       --       59.5%                                     ______________________________________                                    

The active ingredient is thoroughly mixed with the adjuvants and themixture is thoroughly ground in a suitable mill, affording wettablepowders which can be diluted with water to give suspensions of thedesired concentration.

    ______________________________________                                        (b) Emulsifiable concentrate                                                                         (a)    (b)                                             ______________________________________                                        active ingredient      10%    1%                                              octylphenol polyethylene glycol                                                                       3%    3%                                              ether (4-5 moles of ethylene                                                  oxide)                                                                        calcium dodecylbenzenesulfonate                                                                       3%    3%                                              castor oil polyglycol ether                                                                           4%    4%                                              (36 moles of ethylene oxide)                                                  cyclohexanone          30%    10%                                             xylene mixture         50%    79%                                             ______________________________________                                    

Emulsions of any required concentration can be obtained from thisconcentrate by dilution with water.

    ______________________________________                                        (c) Dusts         (a)     (b)                                                 ______________________________________                                        active ingredient  0.1%    1%                                                 talcum            99.9%   --                                                  kaolin            --      99%                                                 ______________________________________                                    

Dusts which are ready for use are obtained by mixing the activeingredient with the carriers, and grinding the mixture in a suitablemill.

    ______________________________________                                        (d) Extruder granulate                                                                           (a)     (b)                                                ______________________________________                                        active ingredient  10%     1%                                                 sodium lignosulfonate                                                                            2%      2%                                                 carboxymethylcellulose                                                                           1%      1%                                                 kaolin             87%     96%                                                ______________________________________                                    

The active ingredient is mixed and ground with the adjuvants, and themixture is subsequently moistened with water. The mixture is extrudedand then dried in a stream of air.

    ______________________________________                                        (e) Coated granulate                                                          ______________________________________                                        active ingredient  3%                                                         polyethylene glycol 200                                                                          3%                                                         kaolin             94%                                                        ______________________________________                                    

The finely ground active ingredient is uniformly applied, in a mixer, tothe kaolin moistened with polyethylene glycol. Non-dusty coatedgranulates are obtained in this manner.

    ______________________________________                                        (f) Suspension concentrate                                                                          (a)    (b)                                              ______________________________________                                        active ingredient     40%    5%                                               ethylene glycol       10%    10%                                              nonylphenol polyethylene glycol                                                                      6%    1%                                               ether (15 moles of ethylene                                                   oxide)                                                                        sodium lignosulfonate 10%    5%                                               carboxymethylcellulose                                                                               1%    1%                                               37% aqueous formaldehyde solution                                                                   0.2%   0.2%                                             silicone oil in the form of a 75%                                                                   0.8%   0.8%                                             aqueous emulsion                                                              water                 32%    77%                                              ______________________________________                                    

The finely ground active ingredient is intimately mixed with theadjuvants, giving a suspension concentrate from which suspensions of anydesired concentration can be obtained by dilution with water.

    ______________________________________                                        Salt solution                                                                 ______________________________________                                        active ingredient     5%                                                      isopropylamine        1%                                                      octylphenol polyethylene glycol                                                                     3%                                                      ether (78 moles of ethylene oxide)                                            water                 91%                                                     ______________________________________                                    

BIOLOGICAL EXAMPLES EXAMPLE 4: Preemergence herbicidal action

In a greenhouse, plant seeds are sown in flower pots of 12-15 cmdiameter. Immediately after sowing, the surface of the soil is treatedwith an aqueous dispersion or solution of the compounds to be tested.Concentrations of 4 kg a.i./ha are employed. The pots are then kept inthe greenhouse at 22°-25° C. and 50-70% relative humidity. The test isevaluated 3 weeks later in accordance with the following rating:

1=plants totally withered

2-3=very pronounced action

4-6=medium action

7-8=insignificant action

9=no action (as untreated controls)

    ______________________________________                                        Preemergence Action                                                           Rate of application: 4 kg a.i./ha                                             Compound   Avena   Setaria   Sinapis                                                                             Stellaria                                  ______________________________________                                        13         6       3         2     2                                          21         4       1         2     2                                          30         7       3         2     2                                          ______________________________________                                    

EXAMPLE 5: Selective preemergence action

A large number of plant seeds are treated with compounds to be tested atdifferent rates of application in the same test procedure as describedin Example 4. Evaluation is made in accordance with the same rating.

    ______________________________________                                        Test Results (preemergence)                                                   Action                                                                        Rate of application                                                           kg a.i./ha     Compound 13                                                    Test plant     0.25   0.12      0.06 0.03                                     ______________________________________                                        wheat          7      8         9    9                                        maize          9      9         9    9                                        Avena fatua    7      8         8    9                                        Alopecurus myos.                                                                             4      4         5    7                                        Echinochloa c.g.                                                                             2      2         3    3                                        Rottboellia ex.                                                                              4      4         7    7                                        Cyperus escul. 1      2         3    3                                        soybeans       6      9         9    9                                        cotton         4      4         4    9                                        Abutilon       1      2         4    4                                        Xanthium Sp.   4      6         6    8                                        Chenopodium Sp.                                                                              2      2         3    3                                        Ipomosa        2      2         3    4                                        Sinapis        1      1         2    3                                        Galium aparine 2      3         3    3                                        Viola tricolor 2      2         2    2                                        ______________________________________                                    

EXAMPLE 6: Postemergence herbicidal action (contact action)

A number of weeds and cultivated plants in pots, both monocots anddicots, are sprayed postemergence, in the 4- to 6-leaf stage, with anaqueous active ingredient dispersion at a rate of application of 4 kga.i./ha, and then kept at 24°-26° C. and 45-60% relative humidity. Thetest is evaluated 15 days after treatment and the action is assessed inaccordance with the same rating as in Example 4.

    ______________________________________                                        Postemergence action                                                          Rate of application: 4 kg a.i./ha                                             Com-          Set-   Lol- Sol-  Sin- Stell-                                   pound Avana   aria   ium  anum  apis aria  Phaseolus                          ______________________________________                                        13    7       6      4    1     2    3     4                                  21    3       3      3    2     3    4     3                                  30    7       6      4    6     3    7     7                                  ______________________________________                                    

EXAMPLE 7: Selective postemergence action

A large number of plants are treated with the compounds to be tested atdifferent rates of application in the same test procedure as describedin Example 6. Evaluation is made using the same rating as in Example 4.

EXAMPLE 8: Inhibition of sprouting in stored potatoes

A number of commercially available potatoes of the "Urgenta" variety,without sprouts, are washed and dried. The potatoes are then immersed inemulsions of the compounds to be tested in different concentrations,placed on filter paper in plastic dishes, and kept in the dark at 14°and 21° C. and 50% relative humidity. Evaluation is made 34 days afterapplication.

The percentage weight loss of the tubers and the weight of the sproutscompared with untreated controls are simultaneously determined.

In this test, a number of compounds of the formula I inhibited sproutingcompletely. At the same time the weight loss of the potatoes was lessthan 10% of the weight loss of the controls.

EXAMPLE 9: Growth inhibition of tropical cover crops

The test plants (centrosema plumieri and centrosema pubescens) arereared until fully grown and then cut back to a height of 60 cm. Theplants are sprayed 7 days later with an aqueous emulsion of the compoundto be tested. The test plants are kept at 70% relative humidity and 6000lux artificial light for 14 hours per day, at day temperatures of 27° C.and night temperatures of 21° C. The test is evaluated 4 weeks afterapplication.

In this test, the new growth of plants treated with a number ofcompounds of the formula I is markedly reduced (less than 20%), withoutdamage being caused to the test plants.

What is claimed is:
 1. A compound selected from the group consisting ofa sulfonylurea of the formula: ##STR13## wherein X is oxygen orsulfur;R₂ is hydrogen, chloro or fluoro; and R₃ is chloro, fluoro,methyl, ethyl, methoxy, ethoxy, isopropoxy or chloromethyl; andthealkali metal, alkaline earth metal, organic amine and quaternary saltsthereof.
 2. A compound according to claim 1 wherein R₂ is hydrogen.
 3. Acompound according to claim 1, wherein X is oxygen. 4.N-(2-Difluoromethoxyphenylsulfonyl)-N'-(4-chloro-6-methyl-pyrimidin-2-yl)ureaaccording to claim
 1. 5.N-(2-Difluoromethylthiophenylsulfonyl)-N'-(4-chloro-6-methoxy-pyrimidin-2-yl)ureaaccording to claim
 1. 6.N-(2-Difluoromethoxyphenylsulfonyl)-N'-(4-chloro-6-methoxy-pyrimidin-2-yl)ureaaccording to claim
 1. 7. A herbicidal and growth regulating compositionwhich comprises an effective amount of at least one compound accordingto claim 1, together with a suitable carrier therefor.
 8. A method ofcontrolling undesired plant growth, which method comprises applyingthereto or to the locus thereof a herbicidally effective amount of acompound according to claim
 1. 9. A method of suppressing plant growth,which method comprises applying thereto or to the locus thereof aneffective amount of a compound according to claim
 1. 10. A methodaccording to claim 8 of selectively controlling weeds in crops ofcultivated plants, which method comprises applying the compoundpremergence or postemergence.
 11. A method according to claim 9 ofsupressing plant growth beyond the two-leaf-stage, which methodcomprises applying the compound preemergence.